The Bharatiya Janata Party is contemplating to move a no-confidence motion against the United Progressive Alliance government through one of the smaller parties of the BJP-led National Democratic Alliance, party sources said.

BJP president Rajnath Singh has convened a meeting of senior party leaders at 5 pm on Tuesday to discuss how one of the NDA constituents could be convinced to bring a no-confidence motion, according to the sources.

"BJP cannot vote with the Left parties against the government as they are toeing an anti-US line which is in contravention with our party's stand," a BJP leader told PTI.

The party is not opposed to the Indo-US nuclear deal per se but is opposed to it in its present form, he said.

Tuesday's meeting will also discuss the possibility of meeting President Pratibha Patil [Images] after the Left parties withdraw support on Wednesday morning.

"We are also discussing whether an emissary should be sent to the Left parties to work together on toppling the UPA government," the BJP leader said.

Earlier in the day, Rajnath Singh said the prime minister should seek a vote of confidence in the Lok Sabha.

He termed the UPA-Left alliance 'unnatural and unholy'.

"This alliance was formed only to oppose the BJP. It had to meet the fate it is destined. It was only a matter of time," he said.